A debugging developer identifies, isolates, and fixes issues or bugs in software or computer systems. They utilize various testing methods and tools to pinpoint where the malfunction is happening. Once the bug is identified, they correct the code, test it to ensure the issue is resolved and the software runs smoothly. They also document the problem and the solution for future reference. In many cases, debugging developers also work to prevent bugs by designing the system in a way that minimizes the chances of errors. They also continuously improve and update the software to ensure optimal performance.